GC Analysis of Polynuclear Aromatic Hydrocarbons (PAHs) in Butter on SLB®-35ms after SPE using Supelclean™ EZ-POP NP
Materials
SPE tube or plate
related product
Inlet Liner, Split/Splitless Type, Single Taper Fast FocusLiner™ Design (wool packed)
pkg of 1 eastandard
CONDITIONS
sample preparation
SPE (Solid Phase Extraction)
sample/matrix
butter
SPE tube/cartridge
Supelclean EZ-POP NP, 2.5 g/12 mL (54341-U)
extraction process
0.5 gm melted butter, diluted to 1 mL in cyclohexane
condition
10 mL acetone, dry 10 min at -10 to -15" Hg
sample addition
0.5 mL butter in cyclohexane
elution
2 x 10 mL acetonitrile
eluate post-treatment
add 5 mL water to eluant, and backextract with 2 x 10 mL aliquots of hexane. concentrate hexane extract to 1 mL
sample preparation
Supelclean LC-Si, 500 mg/3 mL, condition: 3 mL acetone, dry 10 min; then 6 mL hexane, load: concentrated hexane extract, elute: 10 mL hexane, concentrate extract to 1 mL
column
SLB-35ms, 30 m x 0.25 mm I.D., 0.25 μm (29804-U)
oven
60°C (1 min), 20 °C/min to 340°C (10 min)
inj. temp.
300 °C
detector
MSD-SIM (MS source temp.: 250°, MS quads temp.: 200°C)
MSD interface
330 °C
scan range
SIM
carrier gas
helium, 1 mL/min constant flow
injection
0.5 μL pulsed splitless (60 psi until 0.75 min; splitter open at 0.75 min)
liner
2 mm I.D. FocusLiner with taper
Description
Analysis Note
PAHs are ubiquitous in the environment, resulting from both natural and manmade sources of combustion. Farm animals such as cows can become exposed to them through both consumption of contaminated feed and water, and inhalation of contaminated atmosphere. Consequently, these compounds can be present in dairy products produced from cow′s milk such as cheese and butter.
In this application, EZ-POP NP SPE was used as part of an extraction and cleanup procedure for the analysis of PAHs in butter by GC/MS-SIM. After EZ-POP NP extraction, a secondary cleanup was done using silica gel. This produced an extract with low GC/MS background.
Other Notes
Sample pretreatment: 0.5 gm melted butter, diluted to 1 mL in cyclohexane
Legal Information
SLB is a registered trademark of Merck KGaA, Darmstadt, Germany
Supelclean is a trademark of Sigma-Aldrich Co. LLC